American released from Iran describes constant surveillance

Matthew Trevithick had been studying Farsi at Tehran University when he was arrested and held for 40 days in the notorious Evin prison, accused of trying to overthrow the government. Trevithick, one of the five Americans set free by Iran in mid-January, joins Hari Sreenivasan to recount his experience in solitary confinement and his feeling of constant surveillance during his time in the country.